Grinding meat from large chunks into hamburger and the like typically requires repeated grinding operations to successively reduce the meat to the desired size increment, such as for hamburger. It has also long been known that meat grinding can generate numerous bone chips and gristle pieces (hereinafter called bone chips) that pass through with the final ground product and which are undesirable and/or even dangerous to the consumer of the product when eaten. To avoid the bone chip problem, large users of ground meat products, such as fast food chains and the like, generally utilize bone chip removal means in the grinding of the meat products furnished to the restaurants.
It is known in the art to remove bone chips during meat grinding by forming a bone chip collecting pocket in the upstream face of a perforated die plate and forming a radial or spiral groove in the die plate face which is swept by the grinder blades such that bone chips are first collected in the groove and then directed into the collecting pocket. U.S. Pat. No. 4,004,742 are removed from the grinder by periodically disassembling the discharge end of the grinder and dumping the bone chips from the collection pocket. More recently such apparatus has been improved by forming a groove in the auger shaft which extends through a hub in the die plate for communicating bone chips from the collection pocket, through the die plate and to a hose connected to the hub on the downstream side of the die plate. An arrangement of this type is disclosed in U.S. application Ser. No. 328,902 filed Dec. 9, 1981, and now abandoned, and typically is installed at the discharge end of the final grinder in a multi-stage or piggyback grinding set up.
Heretofore, however, bone chip removal means have not been susceptible to wide spread use by small meat users, such as individual supermarkets and meat lockers. Supermarkets, for example, commonly grind their own meat and utilize baggers, cubing devices, or other apparatus at the discharge of the meat grinding device for packaging relatively small packages of the ground meat or for forming the ground meat product into cubes, or the like. The bone chip tube extending from the downstream side of the perforated grinder plate at the discharge end of the piggyback grinding apparatus prevents the effective or efficient use of baggers, cubers or the like. Even when the ground meat is to be discharged onto a platter for sale in the supermarket, the bone chip removal tube impedes the desired manner in which the ground meat is deposited on the platter and hence is deemed undesirable even in that instance. The meat does not discharge onto the platter with the fluff or bloom customary of freshly ground meat, and desirable from a marketing standpoint in supermarkets. Instead, the meat is discharged rather haphazardly on, about, and on opposite sides of the central bone chip removal tube.
As a result, it has not been customary for small or medium meat purveyors, such as individual supermarkets and meat lockers, to remove bone chips from meat ground on their own premises. Accordingly, as is customary in such meat grinding operations, numerous bone chips are generated and pass through into the ground products sold to the public by such meat purveyors, and this in turn, results in many complaints, dissatisfied customers, and costly damage claims by persons who are in fact injured or irritated by such bone chips. Consequently, a need has long existed for a means permitting effective bone chip removal by such meat purveyors.